Ship's propulsion plant

Claim 2

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling having an impeller and a turbine wheel, said impeller being rigidly connected to said drive shaft and said turbine wheel being rigidly connected to said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft; and control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; and means for directly transmitting propulsion torque of said engine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value.

Claim 3

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling having an impeller and a turbine wheel, said impeller being rigidly connected to said drive shaft and said turbine wheel being rigidly connected to said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft; and control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; and means for directly transmitting propulsion torque of said engine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value.

Claim 4

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling having an impeller and a turbine wheel, said impeller being rigidly connected to said drive shaft and said turbine wheel being rigidly connected to said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft; and control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; and means for directly transmitting propulsion torque of said engine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value.

Claim 5

The ship''s propulsion plant according to claim 1 wherein the limiting value of the reverse torque is in the range of the no-load braking torque of said engine.

Claim 6

The ship''s propulsion plant according to claim 1 wherein: said means for transmitting propulsion torque and for automatically disengaging said one-way safety coupling element comprises a coarse pitch screw thread; and said one-way safety coupling element comprises an axially movable gearshift sleeve adapted to be coupled to one element of said hydrodynamic coupling by means of said coarse pitch screw thread; said by-pass coupling further comprising a spur-toothed gear for connecting said gearshift sleeve to the other element of said hydrodynamic coupling, one of said elements of said hydrodynamic coupling being connected to said drive shaft and the other being rigidly connected to said driven shaft.

Claim 7

The ship''s propulsion plant according to claim 3 wherein said coarse pitch screw thread forces said gearshift sleeve into the engaged position when said control means is shifted to transmit the propulsion torque of said engine to said propeller, and said coarse pitch screw thread displaces said gearshift sleeve axially to a disengaged position under the influence of reverse torque of said predetermined value.

Claim 8

The ship''s propulsion plant according to claim 4, said by-pass coupling further comprising torque limiting means coupled between said control device and said gearshift sleeve to prevent disengagement of said gearshift sleeve until the reverse torque has reached at least said predetermined value, said coarse pitch screw thread acting against said torque limiting means to axially displace said gearshift sleeve.

Claim 9

The ship''s propulsion plant according to claim 5 wherein: said by-pass coupling is mechanically shiftable; said torque limiting means comprises a spring link; and said control means for shifting said by-pass coupling comprises a mechanical linkage coupling said spring link to said gearshift sleeve.

Claim 10

The ship''s propulsion plant according to claim 5 wherein: said by-pass coupling is mechanically shiftable; said torque limiting means comprises a pressure limiting valve; and said control means for shifting said by-pass coupling comprises a mechanical linkage coupling said pressure limiting valve to said gearshift sleeve.

Claim 11

The ship''s propulsion plant according to claim 1 wherein said by-pass coupling is accommodated inside the housing of said hydrodynamic coupling.

Claim 12

The ship''s propulsion plant according to claim 3 wherein said gearshift sleeve and one of said shafts are formed with mating spur-toothed gear coupling elements, the confronting face of one of said spur-toothed gear coupling elements being formed with deflection bevels to prevent engagement of said by-pass coupling whenever the element of said hydrodynamic coupling connected to said propeller overruns the element of said hydrodynamic coupling connected to said engine.

Claim 13

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling connected between said drive shaft and said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft; control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; means for transmitting propulsion torque of said enGine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value, said means for transmitting propulsion torque and for automatically disengaging said one-way safety coupling element comprises a coarse pitch screw thread, said one-way safety coupling element comprises an axially movable gearshift sleeve being coupled to one element of said hydrodynamic coupling by means of said coarse pitch screw thread; a spur-toothed gear for connecting said gearshift sleeve to the other element of said hydrodynamic coupling, one of said elements of said hydrodynamic coupling being connected to said drive shaft and the other being connected to said driven shaft; and torque limiting means coupled between said control means and said gearshift sleeve to prevent disengagement of said gearshift sleeve until the reverse torque has reached at least said predetermined value, said coarse pitch screw thread acting against said torque limiting means to axially displace said gearshift sleeve, said coarse pitch screw thread forcing said gearshift sleeve into the engaged position when said control means is set to transmit the propulsion torque of said engine to said propeller, and, with the same setting of said control means said coarse pitch screw thread displacing said gearshift sleeve axially to a disengaged position under the influence of reverse torque exceeding said predetermined value; and a pressure-fluid source; wherein said torque-limiting means comprises a pressure limiting valve, said gearshift sleeve and one of said shafts are mutually constructed as a double-acting piston and cylinder arrangement, said by-pass coupling is hydraulically shiftable, and said control means for shifting said by-pass coupling comprises hydraulic transmission means coupling said pressure-fluid source and said pressure limiting valve to said piston and cylinder arrangement to thereby control relative axial motion between said piston and said cylinder.

Claim 14

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling connected between said drive shaft and said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft; control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; means for transmitting propulsion torque of said enGine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value, said means for transmitting propulsion torque and for automatically disengaging said one-way safety coupling element comprises a coarse pitch screw thread, said one-way safety coupling element comprises an axially movable gearshift sleeve being coupled to one element of said hydrodynamic coupling by means of said coarse pitch screw thread; a spur-toothed gear for connecting said gearshift sleeve to the other element of said hydrodynamic coupling, one of said elements of said hydrodynamic coupling being connected to said drive shaft and the other being connected to said driven shaft; and torque limiting means coupled between said control means and said gearshift sleeve to prevent disengagement of said gearshift sleeve until the reverse torque has reached at least said predetermined value, said coarse pitch screw thread acting against said torque limiting means to axially displace said gearshift sleeve, said coarse pitch screw thread forcing said gearshift sleeve into the engaged position when said control means is set to transmit the propulsion torque of said engine to said propeller, and, with the same setting of said control means said coarse pitch screw thread displacing said gearshift sleeve axially to a disengaged position under the influence of reverse torque exceeding said predetermined value; and a pressure-fluid source; wherein said torque-limiting means comprises a pressure limiting valve, said gearshift sleeve and one of said shafts are mutually constructed as a double-acting piston and cylinder arrangement, said by-pass coupling is hydraulically shiftable, and said control means for shifting said by-pass coupling comprises hydraulic transmission means coupling said pressure-fluid source and said pressure limiting valve to said piston and cylinder arrangement to thereby control relative axial motion between said piston and said cylinder.

Claim 15

The ship''s propulsion plant according to claim 10 and further comprising axial stops for limiting the axial motion of said gearshift sleeve.

Claim 16

The ship''s propulsion plant according to claim 10 wherein said hydraulic transmission means comprises an engagement channel coupled between said control means and one side of said double-acting piston and cylinder arrangement, and a disengagement channel coupled between said control means and the other side of said double-acting piston and cylinder arrangement.

Claim 17

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling connected between said drive shaft and said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft, said by-pass coupling being hydraulically shiftable; and control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; and means for transmitting propulsion torque of said engine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value, said one-way safety coupling element comprises a gearshift sleeve, said gearshift sleeve and one of said shafts being mutually constructed as a double-acting piston and cylinder arrangement, said gearshift sleeve being formed as the piston element and the cylinder element is formed as part of said shaft, said shaft is formed with engagement and disengagement channels for conducting pressure fluid to said piston and cylinder arrangement under control of said control means through respective pressure-fluid lines.

Claim 18

A ship''s propulsion plant comprising: a propulsion engine; a drive shaft connected to said engine; a propeller; a driven shaft coupled to said propeller; a variable-filling hydrodynamic coupling connected between said drive shaft and said driven shaft; a selectively engageable mechanical coupling to by-pass said hydrodynamic coupling to connect said drive shaft to said driven shaft, said by-pass coupling being hydraulically shiftable; and control means for setting the power of said engine, for setting the filling of said hydrodynamic coupling and for shifting said by-pass coupling; wherein said by-pass coupling comprises: a one-way safety coupling element; and means for transmitting propulsion torque of said engine to said propeller and for automatically disengaging said one-way safety coupling element when reverse torque between said engine and said propeller exceeds a predetermined limiting value, said one-way safety coupling element comprises a gearshift sleeve, said gearshift sleeve and one of said shafts being mutually constructed as a double-acting piston and cylinder arrangement, said gearshift sleeve being formed as the piston element and the cylinder element is formed as part of said shaft, said shaft is formed with engagement and disengagement channels for conducting pressure fluid to said piston and cylinder arrangement under control of said control means through respective pressure-fluid lines.

Claim 19

The ship''s propulsion plant according to claim 13 wherein: said double-acting piston and cylinder arrangement includes a first cylinder volume and a second cylinder volume; said shaft is formed with an alarm channel connected by a first radial branch channel to said first cylinder volume and by a second radial branch channel to said second cylinder volume; said propulsion plant further comprising: an indicating mechanism; and an alarm line connecting said alarm channel to said indicating mechanism; said gearshift sleeve is formed with surface grooves which are axially dimensioned and arranged that said first radial branch channel couples said first cylinder volume to said alarm channel only when said gearshift sleeve is in the fully engaged position and said second radial branch channel couples said second cylinder volume to said alarm channel when said gearshift sleeve is not in the fully engaged position.

Claim 20

The ship''s propulsion plant according to claim 14 wherein: said indicating mechanism includes a servomechanism; said engagement pressure-fluid line includes a pressure-release valve actuated by said servomechanism, said pressure release valve being opened by said servomechanism when the fluid pressure in said alarm channel drops below a predetermined normal value.

Claim 21

The ship''s propulsion plant according to claim 15 wherein: said pressure release valve is additionally openable by manual means; said propulsion plant further comprises a temperature monitor mounted to said engine and being coupled to said servomechanism for actuation thereof.

Claim 22

The ship''s propulsion plant according to claim 14 wherein: said gearshift sleeve and one of said shafts are formed with mating spur-toothed gear coupling elements, the confronting face of one of said spur-toothed gear coupling elements being formed with deflection bevels to prevent engagement of said by-pass coupling whenever the element of said hydrodynamic coupling connected to said propeller overruns the element of said hydrodynamic coupling connected to said engine; said propulsion plant further comprising at least one elastic reservoir connected to said first cylinder volume and capable of holding that amount of fluid displaced from said first cylinder volume by said axial oscillations.